Communication system with relays and communication therein via multi-carriers

Abstract

A system and method for transmitting multi-carriers in a wireless communication system with a relay are provided. The method includes configuring each of downlink carriers that form the multi-carriers as at least one normal sub-frame and at least one backhaul sub-frame; determining one of the downlink carriers that has a maximum number of backhaul sub-frames, as a primary carrier, and other downlink carriers as sub-carriers; and altering a backhaul sub-frame into a normal sub-carrier in the sub-carrier, in response to a normal sub-frame of the primary carrier.

What is claimed is: 
     
       1. A method performed by a base station for communicating via multi-carriers, the method comprising:
 configuring each of downlink carriers that form the multi-carriers as at least one normal sub-frame and at least one backhaul sub-frame; 
 determining one of the downlink carriers that has a maximum number of backhaul sub-frames, as a primary carrier, and other downlink carriers as sub-carriers; and 
 altering a backhaul sub-frame into a normal sub-frame in the sub-carrier, in response to a normal sub-frame of the primary carrier, 
 wherein the backhaul sub-frame is for communication between a relay and the base station. 
 
     
     
       2. The method of  claim 1 , further comprising:
 transmitting link information regarding the downlink carriers and the uplink carriers via respective downlink carriers; and 
 selecting if connecting to the relay using the link information, a reply carrier for receiving control information, created in response to the backhaul sub-frame in the relay, from the uplink carriers, and transmitting configuration information indicating the reply carrier. 
 
     
     
       3. The method of  claim 2 , wherein the reply carrier is selected from the uplink carriers according to the link information if a backhaul frame is configured in the sub-carrier at the same time as a normal sub-frame of the primary carrier. 
     
     
       4. The method of  claim 2 , wherein the reply carrier is selected as a primary carrier corresponding to one of the uplink carriers if a backhaul frame is configured in the primary carrier at a timing point in the downlink carriers. 
     
     
       5. A method performed a relay for communicating via multi-carriers, the method comprising:
 determining one of downlink carriers as a primary carrier, and other downlink carriers as sub-carriers, where the downlink carriers form the multi-carriers and each downlink carrier is configured as at least one normal sub-frame and at least one backhaul sub-frame; 
 selecting if a backhaul sub-frame is configured in the downlink carriers, one of uplink carriers as a reply carrier, and transmitting control information that is created in response to the backhaul sub-frame, 
 wherein the primary carrier has a maximum number of backhaul sub-frames in the downlink carriers, 
 wherein the backhaul sub-frame is for communication between the relay and a base station, and 
 wherein the sub-carriers are configured as a subset of the primary carrier where normal sub-frames are arranged in response to the at least one normal sub-frame of the primary carrier. 
 
     
     
       6. The method of  claim 5 , further comprising:
 receiving link information regarding the downlink carriers and the uplink carriers via respective downlink carriers; and 
 indicating if connecting to the base station using the link information, the respective downlink carriers via the primary carrier or sub-carriers, and receiving configuration information for indicating the reply carrier in response to the respective downlink carriers from the uplink carriers. 
 
     
     
       7. The method of  claim 6 , wherein the reply carrier is selected from the uplink carriers according to the link information if a backhaul frame is configured in the sub-carrier at the same time as a normal sub-frame of the primary carrier. 
     
     
       8. The method of  claim 6 , wherein the reply carrier is selected as a primary carrier corresponding to one of the uplink carriers if a backhaul frame is configured in the primary carrier in the downlink carriers. 
     
     
       9. A base station for communicating via multi-carriers, the base station comprising:
 a transmitter for transmitting signals via the multi-carriers of downlink carriers; 
 a configuring unit for configuring each of the downlink carriers as at least one normal sub-frame and at least one backhaul sub-frame; and 
 a controller for determining one of the downlink carriers that has a maximum number of backhaul sub-frames, as a primary carrier, and other downlink carriers as sub-carriers, and for altering a backhaul sub-frame into a normal sub-frame in the sub-carrier, in response to a normal sub-frame of the primary carrier, 
 wherein the backhaul sub-frame is for communication between a relay and the base station. 
 
     
     
       10. The base station of  claim 9 , wherein the controller transmits link information regarding the downlink carriers and uplink carriers via the respective downlink carriers, and selects if connecting to the relay using the link information, a reply carrier for receiving control information, created in response to the backhaul sub-frame in the relay, from the uplink carriers, and transmits configuration information indicating the reply carrier. 
     
     
       11. The base station of  claim 10 , wherein the reply carrier is selected from the uplink carriers according to the link information if a backhaul frame is configured in the sub-carrier at the same time as a normal sub-frame of the primary carrier. 
     
     
       12. The base station of  claim 10 , wherein the reply carrier is selected as a primary carrier corresponding to one of the uplink carriers if a backhaul sub-frame is configured in the primary carrier in the downlink carriers. 
     
     
       13. A relay for communicating via multi-carriers, the relay comprising:
 a receiver for receiving signals via downlink carriers that form the multi-carriers, where each downlink carrier is configured as at least one normal sub-frame and at least one backhaul sub-frame; 
 a controller for determining one of the downlink carriers as a primary carrier and the others as sub-carriers, and for selecting one of uplink carriers as a reply carrier in response to respective downlink carriers; and 
 a transmitter for transmitting control information that is created in response to the backhaul sub-frame, via the reply carrier, under the control of the controller, 
 wherein the primary carrier has a maximum number of backhaul sub-frames in the downlink carriers, 
 wherein the backhaul sub-frame is for communication between the relay and a base station, and 
 wherein the sub-carriers is configured as a subset of the primary carrier where normal sub-frames are arranged in response to the normal sub-frame of the primary carrier. 
 
     
     
       14. The relay of  claim 13 , wherein the controller
 receives link information regarding the downlink carriers and the uplink carriers via the respective downlink carriers, and indicates if connecting to a base station using the link information, the respective downlink carriers via the primary carrier or sub-carriers, and receives configuration information for indicating the reply carrier in response to the respective downlink carriers from the uplink carriers. 
 
     
     
       15. The relay of  claim 14 , wherein the reply carrier is selected from the uplink carriers according to the link information if a backhaul frame is configured in the sub-carrier at the same time as a normal sub-frame of the primary carrier. 
     
     
       16. The relay of  claim 14 , wherein the reply carrier is selected as a primary carrier corresponding to one of the uplink carriers if a backhaul frame is configured in the primary carrier in the downlink carriers.